MXR Micro Amp M133

I used this as a boost in to an overdrive pedal for a long time. It does what it says, boost the signal. It adds a tiny amount of sparkle(treble) to the signal, so i guess it could be used as a sort of a buffer. Its is a very very tiny amount, i would consider it transparent. I know there is a version with treble/bass control on, and that could come in handy to shape the tone if one would want more control.